Camper Trailers Tech Tips

redarc BC-DC 1220






Redarc BC-DC 1220
install and review


    Redarc have just released a new DC-DC 3 stage 20 amp battery charger. (photos 1 & 2)

    The great thing about this unit is it will accept anything from 9 - 32v DC input. That means you can charge the battery on the camper without having to worry about voltage drop or charge a 12volt battery from a 24v electrical system.

    The unit will work with a choice of three battery types - AGM/Gel, Calcium Calcium or Lead acid and uses a three stage charging process to charge the second battery and its Australian designed and built with a two year warranty.

    The compact size makes it great for the caravan or camper trailer or for mounting to a portable battery box. The unit is also sealed so can be mounted externally or used in a marine application. It also overcomes the problem with load sensing charging systems and regulated voltage control charging systems found on some of the more recently released vehicles.

    I installed one of these units into our 2006 Diesel Prado to charge the Aux battery. The unit is fully sealed so it's fine to mount under the bonnet. I used the Piranha Battery tray from TJM to mount the second battery. (see Photo 3) I then installed the BCDC-1220 on the Driver’s side inner guard, just above the ABS pump. (Photo 4,5&6)

    I am using an 880CCA Calcium battery as my aux, so I was very keen to see how the unit performed charging the Calcium calcium battery.

    On a recent camping trip I ran our Engel fridge for two days, and then went for a couple of hours drive. When I returned to camp the unit had reached the absorb charge stage. I estimate we possible used about 30 - 40 amp hours of power to run the fridge for the first couple of days (2.5 days). Another couple of days followed without driving. We then drove a couple of hours to home and the unit was in float mode when I lifted the bonnet at home.

    I put the volt / amp meter on it, and grabbed a couple of shots of the input and output voltage and amps when running a “test” scenario at home. (Photos 7 -14)




Photo 1 Redarc BCDC 1220 unit Photo 2 Redarc BCDC 1220 Unit Photo 3 Piranha battery tray from TJM


Photo 4 Installed on Prado 1 Photo 5 Installed on Prado 2 Photo 6 Test battery installed (not calcium battery)


Photo 7 Main battery voltage (engine at idle, matches with photo 8) Photo 8 Volts and amps to aux battery Photo 9 Unit in Boost mode


Photo 10 Main battery voltage (engine at idle, matches with photo 11) Photo 11 Volts and amps to Aux battery Photo 12 Main battery voltage (engine at idle, matches with photo 13)


Photo 13 Volts and amps to Aux battery just prior to absorb mode Photo 14 Unit in absorb mode  


 thanks to Rod Luhrs for sharing the install with us


November 2009